(1) Field of the Invention
The present invention relates to thin-film transistor devices and methods of manufacturing the same, and relates particularly to a thin-film transistor device for driving and for switching in an organic electroluminescence (EL) display device and a liquid crystal display device, and to a method of manufacturing the same.
(2) Description of the Related Art
In electronic devices, such as television receivers, which use an organic electroluminescence (EL) display device or a liquid crystal display device, luminescence elements which are arranged in a matrix and configure the organic EL display device or the liquid crystal display are driven by thin-film transistor (TFT) devices.
Top gate (staggered) thin-film transistor devices, for example, are available as such a thin-film transistor device. In addition, a top gate thin-film transistor device includes a source electrode, a drain electrode, a semiconductor layer (channel layer), and a gate electrode which are sequentially stacked on a substrate. Among thin-film transistor devices, thin-film transistor devices using amorphous silicon as the material of the channel layer are common due to ease of manufacturing (see for example Patent Reference 1: Japanese Unexamined Patent Application Publication No. 6-342909).